Predictors of blood pressure at 7-13 years: The “new millennium baby” study

•In this study, some possible independent predictors of blood pressure and BMI in childhood were identified.•Introduction of solid food at 5-6 months of age seemed to be associated with low systolic and diastolic blood pressure.•To the best of our knowledge, this study is the first of its kind.•Children from the Italian Health System Organization were used, providing longitudinal data from birth to 14 years.

Background and aimsThe purpose of this study is to evaluate the association between blood pressure (BP) at 7-13 years of age and body mass index (BMI), early feeding, lifestyle indicators, and parental characteristics.Methods and resultsRetrospective plus cross-sectional cohort study was started in 1294 children born in 2000-2004, right from their birth in primary care settings. Early feeding was estimated by measuring breast-feeding (BF) duration, complementary feeding (CF) introduction time, and lifestyle indicators such as daily screen time and weekly extracurricular sports activity time. Parental education, smoking, and obesity-related diseases were also considered. Multivariable linear regression and mediation analysis were used.CF introduction at 5-6 months of age was a negative predictor of systolic and diastolic BP (mean systolic BP-standard deviation score (SDS) −0.38 [95% CI: −0.47, −0.29] (p < 0.001); mean diastolic BP-SDS −0.32 [95% CI: −0.40, −0.24]) (p < 0.001); BMI was a positive predictor of systolic and diastolic BP (p < 0.001); and parental hypertension was a positive predictor of diastolic BP (p < 0.05). Predictors of mean BMI-SDS at 7-13 years of age were birth weight, screen time, and parental obesity and smoking (p < 0.001). BF had no effect on BP or BMI. Mediation analysis showed virtually no indication of the effect of CF on BP mediated by BMI.ConclusionsCF introduction between 5 and 6 months of age could be associated with low BP at 7-13 years. The effect of CF on BP seems to be independent of BMI. Low screen time is associated with low BMI. CF time may play a role in the occurrence of surrogates of noncommunicable disorders in future.